Basionym:Lecanora epiphora Taylor, London J. Bot.6: 159. 1847; MycoBank MB#388181.
Description. Thallus thin and poorly developed as a waxy, continuous to rimose layer, developing from a smooth blackish hypothallus, not distinctly delimited, effuse; surface yellow-orange, smooth, ± shiny, epruinose, very densely covered by small, granular to ± coralloid isidia, ~50 μm thick. Apothecia typically scarce and frequently absent, dispersed to loosely aggregated, occasionally deforming one another, sessile, up to 1 mm in diam., lecanorine to indistinctly ‘zeorine’ (e.g., the proper margin can occasionally be distinguished as an additional, non-isidiate rim); thalline margin concolorous with the thallus, with age almost entirely dissolved into granular or even ± cylindrical isidia, regularly to irregularly circular in outline, pale yellow to orange, epruinose, C-, K-; proper margin typically ill-defined, deep orange to ferruginous, concolorous with the disc, epruinose, C-, K-; disc flat to slightly convex, deep orange to ferruginous, densely covered by coarse orange pruina, C- (± weakly red, indistinct), K+ purple; epihymenium with orange pigment granules, C- (± orange red intensifying), K+ purple, contiguous with the outer exciple; hymenium hyaline, not inspersed; proper exciple extending laterally from the colorless hypothecium as a ± distinct hyaline layer, apically with orange pigment granules, C- (± orange red intensifying), K+ purple, thalline exciple differentiated into an inner part abundantly filled with trebouxioid photobionts and occasionally few, small, colorless crystals, dissolving in K, and an outer part that with age laterally disintegrates; subhymenium thick, well developed, very pale brown, of intricately interwoven hyphae, structurallydistinct from the narrow, hyaline hypothecium of more parallel hyphae, both not inspersed; asci clavate, Teloschistes-type; ascospores 8/ascus, polaribilocular, narrowly to broadly ellipsoid (9.7–)11.4–16.0(–20.1) × (5.8–)6.9–8.6(–9.2) μm, with a thick, (3.5–)4.4–7.3(–9.4) μm wide septum (n = 46). Pycnidia not observed (in the Galapagos material).
Chemistry. Thallus and apothecia P–, K+ purple, C–, KC–, UV– (dull); with a large proportion of fragilin and a smaller proportion of parietin; additionally chlorinated accessory metabolites such as 7-chloroemodin and 7-chloroemodic acid are occasionally also detected.
Ecology and distribution.Lacrima epiphora occurs in neotropical regions of North, Central and South America (see Wetmore, 2004). In Galapagos, it is one of the most common corticolous species, rarely also occurring on wood or rock, and common throughout the dry zone and lower transition zone, occasionally also in upper transition zone, rarely in the humid zone. It is particularly common on Bursera and Erythrina, typically in wind- and rain-exposed, but often ± shaded habitats.
Notes.Lacrima epiphora is characterized by a densely isidiate, yellow-orange thallus, a relatively pale color due to the high content of fragilin. In Galapagos, according to the ITS sequences obtained here, the species appears closely related to L. galapagoensis and L. aphanotripta. Weber (1986) originally reported it as Caloplaca byrsonimae (Malme) Zahlbr.
Nash, T.H., Ryan, B.D., Gries, C., Bungartz, F., (eds.) 2007. Lichen Flora of the Greater Sonoran Desert Region. Vol 3.
Life habit: lichenized Thallus: crustose, continuous or areolate, without elongated lobes; prothallus: present, black surface: yellowish orange, smooth, isidiate isidia: coralloid, laminal Apothecia: present, adnate, 0.3-1 mm in diam., lecanorine disc: orange, flat, epruinose margin: persistent, flush or slightly raised; thalline margin present or absent, concolorous with thallus; proper margin visible, little lighter than disc parathecium: consisting of radiating hyphae; exciple below hypothecium amorphous epihymenium: golden, K+ red, C- hymenium: hyaline, (60-)70-75 µm tall paraphyses: tip cells not swollen, not branched or with few branches; subhymenium hyaline asci: cylindrical, 8-spored ascospores: hyaline, 2 locules, ellipsoid, 11-14(-15.5) x 5.5-7(-8.5) µm, isthmus 5.5-7 µm, spore end wall thin Pycnidia: present, mostly immersed, ostiole orange Spot tests: apothecial margin K+ red, C-; thallus K+ red, C- Secondary metabolites: unidentified anthraquinones. Substrate and ecology: on wood or occasionally on calcareous rocks World distribution: North, Central and South America Sonoran distribution: Baja California Sur. Notes: Caloplaca epiphora has a thin, areolate, smooth, yellow-orange thallus with orange simple to coralloid isidia, algae in the margin of the apothecia, and no oil in the hypothecium. The quantity of isidia can vary considerably from very abundant to quite rare. The isidia are often short and may appear to be granular soredia but in some protected places on the bark they are usually larger and coralloid. Species 5 has globose isidia, thicker areoles becoming somewhat subsquamulose.